System and method for unified communications threat management (uctm) for converged voice, video and multi-media over ip flows

ABSTRACT

A method and system for unified communications threat management (UCTM) for converged voice and video over IP is disclosed. A computer-implemented method for threat management receives an incoming packet. The incoming packet is broken into sub-packets and fed to a plurality of packet processing engines. Each packet processing engine inspects the sub-packets and annotate the sub-packets with meta-data. The annotated sub-packets are combined and processed by a plurality of application engine to generate a processed packet. The processed packet is classified and stored in a database.

The present application claims the benefit of and priority to U.S.Provisional Patent Application No. 60/952,479 filed on Jul. 27, 2007,entitled “Synchronous Flow Security,” and No. 60/980,990 filed on Oct.18, 2007, entitled “A Fine-Grained Unified Threat Management (UTM)Architecture and System for Converged Voice and Video Flows”, andapplication Ser. No. 12/181,135, entitled “A System and Method forUnified Communications Threat Management (UCTM) For Converged Voice,Video and Multi-Media Over IP Flows”, filed Jul. 28, 2008. U.S.Provisional Patent Applications 60/952,479 and 60/980,990, and U.S.Utility application Ser. No. 12/181,135 are hereby incorporated byreference.

FIELD

The field of the invention relates generally to communication overInternet Protocol (IP). In particular, the present method and system isdirected to unified communications threat management (UCTM) forconverged voice, video, and multi-media over IP flows.

BACKGROUND

The emergence of Voice-over-IP (VoIP) and Unified Communications (UC)technology has caused a fundamental shift in the telecommunicationsindustry. Due to numerous benefits of VoIP/UC systems ranging from lowcost, manageability, pervasiveness of IP communication networks and easyintegration with other IP-based software-enabled services, traditionalPrivate Branch eXchange (PBX)/UC systems are increasingly replaced withtheir IP counterparts. The growing popularity of VoIP/UC networks islargely influenced by two benefits: cost savings achieved by migrationfrom Public Switched Telephone Network (PSTN) to VoIP networks and theflexibility of adding new services and applications to the standardtelephony platform. The underlying common IP-based communicationplatform enables richer application and services than were otherwisepossible. The migration from PSTN to VoIP fundamentally has changed thecommunications landscape and the way various end-nodes of a networkcommunicate with one another or with applications.

However, massive deployment of VoIP/UC faces challenges that need to beeffectively addressed to gain widespread adoption. VoIP/UC solutionproviders need to provide high quality, reliability and securitystandards that traditional PSTNs offer. Developing a robust architecturethat adheres to these constraints is a challenging task.

A number of recent studies showed that nearly half of VoIP/UC serviceproviders planning to deploy VoIP/UC networks affirm that currentnetworks and applications are inherently insecure. The security issue isa major concern for VoIP/UC service providers because securityvulnerabilities are not yet well understood, and preventive measures forsecurity have not yet been fully adopted.

VoIP/UC security is vastly different from conventional data security dueto the real-time nature of VoIP/UC communications. Real-timecharacteristics include: zero down time, near close to 100%Quality-of-Service (QoS), reliability, low latency overheads andsecurity. VoIP/UC solutions need to comply with the complex VoIP/UCnetwork standards involving a myriad of protocols, applications anddevices while maintaining the dependency with existing PSTN systems. AVoIP/UC network is a converged network of PSTN and IP-telephony, thus itis subject to security threats that potentially emanate from either oneof the two networks. Due to the number of potential threat vectorsarising from the convergence of PSTN and IP-telephony networks, theunderlying security protection measures based on either one of thenetwork architectures are not well suited to counterattack most of them.In addition, VoIP/UC networks require close-to-perfect reliabilitybecause of the real-time requirement for voice communication. Fordata-only communication, a typical response to a security attackinvolves a human intervention, which incurs significant time delays toreduce the scope of the threat and provides appropriate mitigationsolutions. Unlike data-only communication, human interventions areinadequate for VoIP/UC communications, which require a real-timeresponse to security threats.

VoIP/UC communication is highly sensitive to QoS parameters. A VoIP/UCsecurity solution causing a noticeable loss in voice quality isunacceptable. Any interruption in the flow of packets, reassembly orjitter impacts the quality of voice conversation. For datacommunication, the lost data is retransmitted causing additional delay.While this may be acceptable for simple data communication,retransmission in the VoIP/UC realm implies that the caller has torepeat the lost voice message or reinvoke the UC service, which makesany solution that introduces time delay by retransmission anunacceptable solution.

Latency is another factor to consider when deploying VoIP/UC solutions.Modern data security solutions employ encryption and/or deep-packetinspection methods to improve security. Both of these methods introduceadditional time delays and jitters to VoIP/UC packet streams, thusimpacting the overall QoS of voice steams.

VoIP/UC networks interacting with and depending on existing PSTNnetworks pose a new set of challenges such as attack entry vectors andapplication threats. With a myriad of deployment solutions andarchitectures spanning the VoIP and traditional PSTN networks, thecomplexity of threat detection and mitigation grows exponentially.

The emergence of Voice-over-IP (VoIP), Unified Communications (UC) andCommunications Enabled Business Process (CEBP) solutions has changed theway that enterprises communicate with each other. The convergence ofvoice and data into a single IP network creates a cost-effectivetransport mechanism that enables a new set of services. Voice, which waspreviously confined to a separate legacy network (e.g., PSTN), becameubiquitous and plays an integral role in communication among andbridging disparate entities. These entities include multiple users anduser groups both inside and outside the enterprise, as well as advancedapplications that enable communication with other entities anywhere,anytime with any device. The converged VoIP, UC and CEBP solutions needto comply with a myriad of protocols, applications and devices includingthe ones on legacy voice networks. These compliance requirements exposethe convergent solutions to threat vectors that emanate from multipleentry points and pose formidable challenges with security andreliability.

SUMMARY

A method and system for unified communications threat management (UCTM)for converged voice and video over IP is disclosed. Acomputer-implemented method for threat management receives an incomingpacket. The incoming packet is broken into sub-packets and fed to aplurality of packet processing engines. Each packet processing engineinspects the sub-packets and annotates the sub-packets with meta-data.The annotated sub-packets are combined and processed by a plurality ofapplication engine to generate a processed packet. The processed packetis classified and stored in a database.

The above and other preferred features, including various novel detailsof implementation and combination of elements, will now be moreparticularly described with reference to the accompanying drawings andpointed out in the claims. It will be understood that the particularmethods and circuits described herein are shown by way of illustrationonly and not as limitations. As will be understood by those skilled inthe art, the principles and features described herein may be employed invarious and numerous embodiments without departing from the scope of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included as part of the presentspecification, illustrate the presently preferred embodiment of thepresent invention and together with the general description given aboveand the detailed description of the preferred embodiment given belowserve to explain and teach the principles of the present invention.

FIG. 1 illustrates an exemplary enterprise network including variousserver farms, according to one embodiment;

FIG. 2 illustrates an exemplary Session Initiation Protocol (SIP) flowinvolving a SIP call, according to one embodiment;

FIG. 3 illustrates an exemplary UCTM security solution that correlatesprotocol, endpoint and application transaction states across signaling,media, modules, applications and Communications Enabled Business Process(CEBP), according to one embodiment;

FIG. 4 illustrates exemplary VoIP threats categorized by common attacktypes with similar entry methods and common vulnerability exploitation,according to one embodiment;

FIG. 5 illustrates an exemplary architecture for a UnifiedCommunications threat management (UCTM) system, according to oneembodiment;

FIG. 6 illustrates a layered system architecture for an exemplary UCTMsystem, according to one embodiment; and

FIG. 7 illustrates an exemplary computer architecture for use with thepresent system, according to one embodiment.

It should be noted that the figures are not necessarily drawn to scaleand that elements of similar structures or functions are generallyrepresented by like reference numerals for illustrative purposesthroughout the figures. It also should be noted that the figures areonly intended to facilitate the description of the various embodimentsdescribed herein. The figures do not describe every aspect of theteachings disclosed herein and do not limit the scope of the claims.

DETAILED DESCRIPTION

A system and method for Unified Communications threat management (UCTM)for converged voice and video over IP is disclosed. Each of the featuresand teachings disclosed herein can be utilized separately or inconjunction with other features and teachings to provide a method andsystem for UCTM for converged voice and video over IP. Representativeexamples utilizing many of these additional features and teachings, bothseparately and in combination, are described in further detail withreference to the attached drawings. This detailed description is merelyintended to teach a person of skill in the art further details forpracticing preferred aspects of the present teachings and is notintended to limit the scope of the claims. Therefore, combinations offeatures disclosed in the following detailed description may not benecessary to practice the teachings in the broadest sense, and areinstead taught merely to describe particularly representative examplesof the present teachings.

In the following description, for the purposes of explanation, specificnomenclature is set forth to facilitate an understanding of the variousinventive concepts disclosed herein. However, it will be apparent to oneskilled in the art that these specific details are not required in orderto practice the various inventive concepts disclosed herein.

The present invention also relates to an apparatus for performing theoperations herein. This apparatus may be specially constructed for therequired purposes, or it may comprise a general-purpose computerselectively activated or reconfigured by a computer program stored inthe computer. Such a computer program may be stored in acomputer-readable storage medium, such as, but is not limited to, anytype of disk including floppy disks, optical disks, CD-ROMs, andmagnetic-optical disks, read-only memories, random access memories,EPROMs, EEPROMs, magnetic or optical cards, or any type of mediasuitable for storing electronic instructions, and each coupled to acomputer system bus.

The methods presented herein are not inherently related to anyparticular computer or other apparatus. Various general-purpose systemsmay be used with programs in accordance with the teachings herein, or itmay prove convenient to construct more specialized apparatus to performthe required method steps. The required structure for a variety of thesesystems will appear from the description below. In addition, the presentinvention is not described with reference to any particular programminglanguage. It will be appreciated that a variety of programming languagesmay be used to implement the teachings of the invention as describedherein.

Moreover, the various features of the representative examples and thedependent claims may be combined in ways that are not specifically andexplicitly enumerated in order to provide additional useful embodimentsof the present teachings. It is also expressly noted that all valueranges or indications of groups of entities disclose every possibleintermediate value or intermediate entity for the purpose of originaldisclosure, as well as for the purpose of restricting the claimedsubject matter. It is also expressly noted that the dimensions and theshapes of the components shown in the figures are designed to help tounderstand how the present teachings are practiced, but not intended tolimit the dimensions and the shapes shown in the examples.

FIG. 1 illustrates an exemplary enterprise network including variousserver farms such as telecommunication server farm 111, Web server farm112, email server farm 113 and database server farm 114, according toone embodiment. Telecommunication server farm 111 includes unifiedmessaging (UM) server 121, presence server 122, conferencing server 123and IP-PBX server 124. UCTM system 105 is placed in front oftelecommunication server farm 111 and acts as a proxy-gateway solutioninspecting both inbound and outbound traffic. UCTM system 105 appliesdifferent security policies to an application running at a server farmin addition to binding the application to an user or a group of users.This allows for applying different security policies at variousendpoints depending on the trust level of the entry user group. Forexample, user groups whose identity are known a priori such as a mobileoffice employee or OEM partner connecting through Skype or SSL-VPNaccess may benefit from services providing flexible security policies.

Communication flows arrive at the forefront of enterprise network 100from various external networks including service provider network 161and telecommunication network 162. Such communication flows may arriveat firewall 101 from network devices or nodes having intention forsecurity attack. Some types of security attacks are blocked or filteredby a series of enterprise routers 102, 103, Denial of Service (DOS)protection 152 or Secure Sockets Layer protection 153.

A typical UC service such as a Web conferencing session hosted byconferencing server 123 requires a valid registration, and communicationflows potentially spanning multiple server farms. In particular,communication flows to telecommunication servers are subject to variouslevels of protection; communication flows 111 indicate unprotectedcommunication flows. Communication flows 113 are protected by UCTMsystem 105 whereas communication flows 112 are protected by othervendors 106 for existing applications/servers, typically dedicated to asingle application/server.

FIG. 2 illustrates an exemplary Session Initiation Protocol (SIP) flowinvolving a SIP call, according to one embodiment. User Agent (UA) 251(sip:alice@atlanta.com) calls another UA 252 (sip:bob@biloxy.com). TheSIP call starts with an INVITE message 203 from UA 251 to UA 252. SIPproxy server 263 (sip.atlanta.com) queries DNS server 261 to resolve UA252's domain (biloxy.com) via 205 and 206 and requests SIP redirectserver 262 to redirect UA 251's call request when UA 252 is outside therange of the SIP proxy server 263. After UA 251's call request arrives(sip.biloxy.com) either via SIP proxy server 263 or SIP redirect server262 over network 299, SIP proxy server 264 queries location service 265to resolve UA 252's internal address. UA 252's phone rings and, whenfollowed by an affirmative response by UA 252, the media connection flowis directly established between UA 251 and 252.

UA's devices (phones, PDAs, etc.) are registered with a registrationserver prior to using SIP calls. For example, UA 252's phone number isregistered with registration server 266 and its registration informationis stored in location service 265. When an incoming call arrives, SIPproxy server 264 queries location service 265 to identify UA 252's phonenumber where the incoming call is redirected to.

Unified Communication threat management (UCTM) is a highly specializedsolution designed for providing complete protection, visibility andcontrol for voice-, video-, and multimedia-over-IP traffic. According toone embodiment, UCTM system 105 performs a blended approach to securitycombining stateful inspection, protocol anomaly detection and intrusionprevention with application-aware techniques such as voiceDenial-Of-Service (DOS) protection, voice SPAM prevention and threatprotection and policy enforcement for UC and CEBP applications. Inaddition, UCTM system 105 meets real-time traffic needs of the UCservices. As a result, UCTM system 105 combines security services fordata and voice to provide not only comprehensive protection against aplethora of voice, video and multimedia IP threats but also completecontrol and visibility of real-time traffic.

According to one embodiment, UCTM system 105 satisfies five categoriesor criteria to effectively address VoIP/UC security and deploymentchallenges.

Category I (real-time requirements) requires high reliability. Forexample, 99.999% uptime having less than 5 minutes of downtime per yearneeds to be guaranteed. In addition, real-time requirements also includelow latency for media and signaling and stringent Quality-of-Service(QoS) jitter having less than 100 microseconds for media and 2milliseconds for signaling.

Category II (security requirements) requires low tolerance tofalse-positives and false-negatives. Under this category, callre-attempts are not acceptable. UCTM system 105 employs encryptedtraffic (e.g., SIP/TLS, SRTP).

Category III (technology requirements) requires capabilities for deeppacket inspection from Layer 3 to Layer 7 VoIP and UC traffic. UCTMsystem 105 employs a heterogeneous architecture having both pro-activeand reactive solution elements. It also maintains multiple levels ofcall state with adaptive behavioral learning of both UC applications andVoIP endpoints. It further provides advanced correlation of protocolstate with security events across the different layers and securitymodules. Category III requirements comprehensively address VoIP, UC andCEBP application security threats such as SIP/SCCP/H.323 protocolanomaly detection, Intrusion Prevention System (IPS), voice DOS and SPAMover Internet Telephony (SPIT) prevention, eavesdropping, toll fraud,number harvesting, Man-in-the-middle (MITM) attacks as well as UC-awarepolicy and incident management system.

Category IV (enterprise focus) requires deeper interoperability withdisparate systems. Complex services spanning multiple protocols areemployed. UCTM system 105 employs zero-touch deployment requirementunder this category.

Category V (UC and CEBP communications focus) requires tight integrationwith IP-PBX and other communication infrastructure elements for the easeof deployment and manageability. Third party vendor solutions providingUC and SOA services (e.g., Microsoft, SAP, BEA, IBM) are easilyintegrated. Under Category V, all VoIP and UC traffic are visible, andcontrols of all UC services, applications and assets are provided.

Intrusion Detection System (IDS) and Intrusion Prevention System (IPS)vendors are strong in enterprise focus (Category IV) but are not wellsuited to meet real-time requirements (Category I). They have a highdegree of false-positives (Category II) and lack technological elements(e.g., advanced call state correlation) required to address complexblended threats that may span multiple VoIP/UC protocols (Category III).Conventional data security solutions also lack UC and CEBP communicationfocus (Category V).

UTM vendors provide solutions that are very similar to that of IDS/IPSvendors but lack best-of-breed solution and technological elements. Theyprovide solutions that are better suited for price sensitive small andmedium businesses (SMB) at a significantly lower price. UTM devices aremired in performance related issues and do not provide solutions underCategories II, III and V.

Session Border Controller (SBC) vendors provide security solutions thatare very strong in Category I (real-time) and adequate for carrier andedge (or border) protection deployments. They are, however, notenterprise-focused, therefore lack the necessary technological andsolution elements required for providing adequate UC and CEBPapplication security (Categories III, IV and V).

Existing IP-PBX players are primarily focused on providing end-uservoice solutions and equipment. Their solutions are strong in real-time(Category I), enterprise (Category IV) and UC focus (Category V) but arenot focused on providing security solutions (Category II and III).

Conventional security solutions such as IDS/IPS appliances, networkfirewalls, UTM and/or SBC vendors are not well suited for addressing thecomplex VoIP and UC security requirements and deployment challenges.

FIG. 3 illustrates an exemplary UCTM security solution that correlatesprotocol, endpoint and application transaction states across signaling,media, modules, applications and CEBP, according to one embodiment.Signaling layer 302 includes VoIP protocols 313 such as SIP, H.323,Media Gateway Control Protocol (MGCP) and Skinny Call Control Protocol(SCCP) as well as media protocols 303 such as Real-time TransportProtocol (RTP) and Secure RTP (SRTP) protocols 314. Modules 304 includecommunications servers 315 such as Office Communications Server (OCS),Live Communications Server (LCS) and IP-PBX servers 124. Exemplary UCTMapplications 305 include Interactive Voice Response (IVR) 316, AutomatedCall Distribution (ACD), conferencing (Web or voice) 123, UnifiedMessaging (UM) 121, collaboration 318 and presence applications 122.CEBP applications 306 are tailored for unique business processes such asfinancial 321, government 322 and healthcare applications 323. Currentsolutions are limited to individual silos but UCTM security solutionprovides a unified solution across signaling, media, modules,applications and CEBP layers. For example, a communication signalwithout deep packet inspection and stateful analysis results in anattack that is not correctly identified or detected.

Several thousand threats for VoIP have been compiled from varioussources, such as VOIPSA group, CERT, BugTraq and other vulnerabilitypostings from several vendors. VoIP deployment is hampered by a varietyof threats at different entry points and attack vectors that exploitweaknesses. Such weaknesses exist in network layer, underlying OS,network protocol, application layer and/or device configuration.

FIG. 4 illustrates exemplary VoIP threats 401 categorized by commonattack types with similar entry methods and common vulnerabilityexploitation, according to one embodiment. Categorizing VoIP threatshelps better understand various VoIP threat vectors such that a commoneffective security solution for each category is formulated.

VoIP device OS vulnerability 411 includes VoIP threats from VoIP devicessuch as IP phones, call managers, gateways, registration and other proxyservers run an operating system (OS). Compromise of the underlying OSleads to an integrity compromise of the VoIP device running the OS. Mostof the VoIP devices run on traditional operating systems (e.g., Windows,Linux, RTOS) that are vulnerable with numerous exploits that arepublicly available. For example, buffer overflow against a device OS isa well-known attack exploiting VoIP Device OS vulnerability.Denial-of-Service (DoS) triggered by fragmented UDP packets is anotherexample under this category.

VoIP device configuration weakness treats 412 refer to the threatspenetrating through VoIP infrastructures due to weaknesses inconfigurations such as open TCP/UDP ports, open file shares with globalread/write permissions or temporary folders with weak permissions, etc.As a result, the services running on the VoIP device become vulnerableto a wide variety of attacks resulting in either a loss of service or acompromise of the VoIP device. For example, a known SIP-based phonetelnet service allows the telnet service to be exploited by an attackerdue to weak password permissions set on the VoIP device. In addition,Simple Network Management Protocol (SNMP) services offered by the VoIPdevice are vulnerable to reconnaissance attacks, and valuableinformation is gathered from an IP phone by using SNMP queries with the“public” community name.

IP/TCP infrastructure weakness threats 413 rely on transport protocolssuch as TCP/IP 311 or UDP 312. The availability of a VoIP/UC servicedepends on the availability of the underlying IP/TCP infrastructure.VoIP protocols rely on TCP and UDP as transport mediums and hence arealso vulnerable to attacks that TCP and UDP are generally exposed tosuch as DOS/DDOS, session hijacking, protocol anomalies, etc. and causean undesirable behavior on the VoIP services.

VoIP protocols implementation vulnerability threats 414 rely on the VoIPprotocols such as SIP, H.323 that are relatively new standards. Both theprotocol specifications and the subsequent implementations need tomature to reduce the overall threat exposure. Examples include parsingerrors, NULL packets, anomalous packets, RFC violations etc. Severalvulnerabilities are discovered in vendor implementations of VoIPproducts that use H.323 and SIP.

According to one embodiment, VoIP application-level threats 415 aregrouped into the following four categories based on various entries andinjection mechanisms: service availability attacks 421, serviceintegrity attacks 422, SPAM over Internet Telephony (SPIT) 423 andeavesdropping attacks 424.

Service availability attacks 421 are focused on disrupting theavailability of VoIP services. The unavailability of a critical servicehas a direct customer impact, lost revenues, unplanned downtimes andmaintenance costs. Such examples include VDOS attacks, remote codeinjection and viruses or worm-based threats. The affected clients areend-user VoIP applications, phones, soft-clients, call managers,registration servers, etc. Due to the real-time nature of VoIPapplications, any disruption in service causes tremendous businessimpact including financial loss and loss of productivity.

Service integrity attacks 422 are focused on compromising the integrityof VoIP services. These attacks are very targeted and usually difficultto detect. These attacks ruin the reputation and brand name of theservice provider, and result in leakage of sensitive information byphishing attacks. Some examples of service integrity attacks includecollaboration session hijacking, redirecting existing mediaconversations to an attacker's machine, classic man-in-the-middle (MITM)attack, broadcast hijacking, identity theft, conversation alteration,impersonation and toll fraud.

SPIT attacks 423 impose potential threats like its email counterpart.With increasing deployment of IP solutions, SPIT is expected to be anattractive choice for spammers due to its low cost and pervasiveness ofthe Internet. Conventional SPAM methods adopted by telemarketers requirea human presence manually dialing the phone numbers and making the voiceconnections. This attack pattern is drastically changed with IPnetworks, as even a simple computer script can flood vulnerablecorporate phone systems with SPAMs.

Eavesdropping attacks 424 allow attackers to obtain sensitive businessor personal information otherwise deemed confidential. The eavesdroppingmechanism exploits intercepting and reading of messages andconversations by an unintended party. Once the information is collectedand translated, various Man-in-the-Middle (MITM) attacks can be launched(e.g., reading, inserting, modifying the intercepted messages). Someexamples include masquerading, registration hijacking, impersonation andreplay attacks.

The last decade has seen a rise in several best-of-breed point securityproducts to overcome the challenges presented by ever changing threatsincluding network firewalls, SSL VPN appliances, DOS protection,anti-virus, IDS/IPS, anti-SPAM and content filtering solutions. All ofthese point products provide best-of-breed protection for the threatsthat they are well adept with. However, these products typically work inisolation in the network with limited end-to-end system visibility andcontrol. Oftentimes, the Layer 3-7 networking stack functions areexecuted multiple times without good inter-communication between them.In addition, each product provides its own management console presentingunique challenges for effective end-to-end network configuration withcorrect policies.

Deployment and management of these point products became a big challengefor enterprise networks. This leads to the rise of Unified ThreatManagement (UTM) solutions that provide several of the above features ina single box. In general, deploying a single multi-function devicereduces costs and overall management. Each of the security functionsworks in loosely coupled form but the common UTM framework provides acentral management console of managing and configuring the product.There are widely perceived deployment challenges faced by current UTMsolutions: performance bottlenecks, scalability, not best-of-breedsolutions, architectural limitations and reliability. Current UTMsolutions are also very much limited to enterprise data networks.

Voice/video, multimedia and other Unified Communications (UC) pose adifferent set of challenges. Real-time communication mandates highreliability and requires near perfect latency, low jitter with near-zerofalse-positives and negatives. The real-time requirements presentchallenges for conventional enterprise-focused UTM solutions that aredeployed in data-centric networks.

FIG. 5 illustrates an exemplary architecture for Unified Communicationsthreat management (UCTM) system, according to one embodiment. UCTMsystem 500 is applied to voice, video, multimedia and UC communicationsover IP. The underlying architecture adopts a layered defense approachusing best-of-breed component technologies. UCTM system 500 continuouslyinspects data streams using real-time stream inspection engines thatoperate at transport, real-time and application layers. Meta-datatranslation layer 520 bridges the intelligence betweentransport/real-time layer and application layer to communicate events,results and statistics therebetween.

Incoming packet flows are inspected in the following processes. Anuntrusted flow that comes into the system is first passed totransport/real-time engines 510. Transport/real-time engines 510 havesignature engine 511, rate engine 512, protocol anomaly engine 513,stateful inspection engine 514, real-time monitor engine 515 and proxytermination (B2B UA) engine 516. Incoming flow is broken into multiplesub-flows that are processed asynchronously and in parallel by therespective engines. Once the processing is done, each engine 511-516adds meta-information to the flow annotating the results generated fromits execution. Meta-data translation layer 520 combines all themeta-information coming from the various engines into a single fullyannotated flow. The annotated flow is fed into application engines 530.

Application engines 530 have of Voice DOS/DDOS (VDOS/VDDOS) engine 531,SPIT engine 532, policy engine 533, compliance/privacy engine 534, datavalidation engine 535 and wiretapping engine 536. Application engines530 operate on the fully annotated meta-information providing richcontext to the communication. These application layer engines operate onthe meta-data making them protocol agnostic.

The resultant flows are passed to behavioral learning (BL) and decision(BL&D) engine block 540 for further processing. BL&D engine block 540further analyzes and processes the rich information in the meta-datathat carries hints, recommendations, anomaly events, policy violations,alerts, etc.

According to one embodiment, an untrusted flow 501 is classified intoone of two possibilities: trusted flow 551 and malicious flow 552. Atrusted flow 551 requires no action and is sent to the backend serversfor further processing. A malicious flow 552 requires further actionguided by user-provided configurable remediation options. Exemplaryremediation options include drop packets 561, force retry 562, captureport 563 and honeypot 564. Drop packets 561 include mechanisms thatprevent malicious packets from proceeding further to backendcommunication servers. Force-retry mechanisms 562 challenge the incomingrequests by specifying the credentials of the source of the request.Force-retry mechanisms 562 also include a retry mechanism which retriesthe original request after a time delay. Capture port 563 includesmechanisms that capture the identity of the originating source forfurther forensic analysis. Honeypot 564 includes mechanisms that routemalicious flows to dedicated servers which store all the traffic- andendpoint-related credentials for later post-mortem analysis.

According to one embodiment, BL&D engine block 540 learns legitimate andanomalic flows, and records them into a database as unique and easilyretrievable record entries. According to another embodiment, BL&D engineblock 540 tags the processed and analyzed flows per-session, per-user,per-domain, per-application, per-user/application group to use them forconstructing remediation policy.

The records carry a certain state about the hashed entry and providerich context on its behavior and past usage. For example, an untrustedflow coming into the system but with a matching record entry is droppedinstantaneously with no further action required by any upstream enginesin transport/real-time layer, and meta-data translation layer 520 andapplication layer 640. The learned communication information is fed backto the flow control module 502 via 570 to provide a fast decisionmechanism and to cut processing time of the processing engines.

FIG. 6 illustrates a layered system architecture for an exemplary UCTMsystem, according to one embodiment. According to one embodiment, theunderlying OS is a hardened Linux stack with all the unnecessaryoptional functionalities stripped out. Unnecessary services from the OSare removed, and unnecessary ports and/or applications for accessing theInternet are blocked. Only certified services, ports and application areguaranteed to run while any other processes including processes formalicious intent are prevented and reported. Default least executionprivileges are applied for all open and running services. Adequatebuffer overflow protection is achieved by applying Address Space LayoutRandomization (ASLR) techniques which involve randomization of theprogram and data address space to defeat code injection-based exploitswhich rely on certain key processes and/or libraries loaded at certainknown addresses.

The present system and method prevents a wide variety of attackstargeting VoIP applications and infrastructure. The component enginesinclude various engines in a layered architecture. Transport layer 620includes signature engine 511, rate engine 512 and protocol anomalyengine 513. Real-time layer 630 includes stateful inspection engine 514,real-time monitor engine 515 and proxy-termination engine 516.Application modules layer 640 includes VDOS/VDDOS engine 531, SPITprotection engine 532, policy engine 533, compliance/privacy monitoringengine 534, data validation engine 535 and BL&D engine block 540. BL&Dengine block 540 individually contains several modules 541-547 that areused to track VOIP/UC traffic and application activities.

Signature engine 511 provides reactive protection for vulnerabilitiesthat are not protected by other continuous streaming engines. Reactiveprotection provides protection based on the signature of the source. Avulnerability server continuously monitors threats and vulnerabilities,and the signatures of the monitored threats are updated and becomeavailable to signature engine 511. Vulnerabilities in higher protocolstacks including SIP, SCCP, RTP, H.323 etc. that are not well addressedby continuous streaming engines are captured by signature engine 511.The vulnerability server periodically releases security advisories andsignature updates for vulnerabilities that for some reason are notprotected by continuous streaming engines. Customers using a UCTM system105 download the signature updates from the UCTM system 105's websiteand get adequate protection coverage for critical and recentvulnerabilities affecting their communications infrastructure andsystems.

Rate engine 512 is responsible for ensuring that packet flows conform tothe specified rate flow constraints. For every incoming packet, rateengine 512 inspects the IP/port of the sender and checks to see if anyprior address-of-record (AOR) entry exists. If a prior AOR entry exists,it increments a rate counter based on the time of the previouslyreceived message. Rate engine 512 then checks to see if the updated ratecounter has crossed any configured threshold based on the variousparameters being monitored. If the updated rate counter does not exceedits corresponding threshold for the specific user (or an application),rate engine 512 processes the received packet to continue; otherwiserate engine 512 stops processing the packet further and blocks theconnection flow concluding that the received packet is untrustworthy. Ifthere is no prior AOR entry (i.e. new subscriber), rate engine 512stores all user specific information into a new record entry (e.g., IP,port, call-ID, contact, contact sequence number (CSeq), date) with arate counter initialized. According to one embodiment, a new user fallsinto one of three user profile categories, ‘trusted user,’ ‘untrusteduser’ or ‘unclassified user.’

According to one embodiment, rate engine 512 employs a suite ofremediation steps when a rate counter exceeds a threshold. The receivedpacket may be dropped immediately or after some time. Aretry-after-mechanism may be enforced if the threshold continues toexceed indicating a DOS attack. Alternatively, all the incoming trafficfrom the user/user-group/domain/IP-range may be blocked.

According to one embodiment, each category has different thresholdlevels. For example, an untrusted user has a lower threshold value whencompared to a trusted-user. Each user may be associated with a profilebased on its IP/port, domain name or an AOR if their entries exist inthe database.

According to one embodiment, rate engine 512's policies operate eitherat a user, system-level and are either static or real-time. Staticpolicies may be enforced at either user-level or system-level. Ratecounters are monitored at user-level counting call attempts per second,simultaneous calls open at a time, retransmissions per second.Additionally, specific message counters such as register counter, invitecounter, response counter, error response counter or request counter aremonitored against threshold values. At system-level, number of activesessions (or calls), number of new sessions created, number of peaksessions, number of sessions expired and message counters are monitoredfor violation of rate rules. According to another embodiment, dynamicpolicies are enforced at a specific date, time or hour. For example, ata specific time of the day or on a specific day of a week, call attemptsper user or application are monitored. Dynamic policies may be enforcedwith a combination of date/time/hour rules.

Protocol anomaly engine 513 provides protection against maliciousprotocol message exploitations, forceful insertion of non RFC-compliantcharacters or state transitions that are undefined. Inadequate protocolanomaly protection may lead to simple denial-of-service (DoS) attacks.Exemplary attacks in this category include protocol fuzzing attacks,input fuzzing attacks, insertion of large anomalous packets, abnormalheader or parameter fields.

In addition to protocol anomaly attacks, for protocols such as SIP,extensions to the base RFC draft from various VoIP vendors may raiseissues with interoperability among various VoIP vendor products. Thismay result in unnecessary false-positives unless adequate intelligenceis present which differentiates between a protocol anomaly attack and aninteroperability issue.

According to one embodiment, any illegitimate control or invalidtransitions detected by the protocol anomaly module 513 due to eitherbad inputs or non-conformant messages are silently recorded. All thestate properties including connection, application and sessionproperties are recorded in a proprietary meta-data format and sent to BLengine 541. BL engine 541 performs further analysis on the meta-data andpresents its recommendations back to protocol anomaly engine 513. Therecommendation action is also tied to global remediation policies561-564 that block the traffic, redirect the traffic to honeypot orenforce authentication challenge.

According to one embodiment, the observed heuristics and steps areenforced by BL engine 541 as follows. The meta-data provides detailedinformation of all transport, session and application properties in aprotocol agnostic form. If BL engine 541 detects no prior instance ofthe record, or a matching record found without an exact match of thecurrent observed anomalic properties, BL engine 541 returns a legitimateerror back to the client assuming that the request is a well behaved oneby sending a request failure error (a 4xx error according to SIP). BLengine 541 internally scores all incoming requests into one of the threebuckets; white list contains endpoints that are always detected to bewell behaved, such that incoming requests from them are safe; black listcontains endpoints that are detected to be bad and/or malicious; graylist refers to anything in between. BL engine 541 records the meta-dataof an incoming request into the gray list when an assertive conclusioncannot be made whether the incoming request falls into either the whiteor black list. All gray list entities are intensively tracked and thebar for diagnosing bad activity from them is much higher when comparedto white list entities. This puts this specific instance and endpoint inhigh visibility mode. If future instances of the same activity aredetected, BL engine 541 immediately downgrades the identified record'sstatus to the Black List category and sends an appropriate remediationevent, for example, block, alert, redirection, ignore the endpoint forsome time. BL engine 541 and protocol anomaly engine 513 communicatethrough meta-data and events with specific properties to take theappropriate actions.

Stateful inspection engine 514 runs a finite state machine (FSM) withfull termination and proxy capabilities. The FSM is a SIP and SCCP-basedlogical entity that receives and processes INVITE messages as a useragent server (UAS). It also acts as a User Agent Client (UAC) thatdetermines how the request should be answered and how to initiateoutbound calls. Stateful inspection engine 514 maintains complete callstate, can terminate and reopen new connections in both ingress andegress directions, encrypt and decrypt traffic and participate in allcall requests.

Stateful inspection engine 514 implements the necessary logic to copyall the relevant headers from UAS to UAC and vice versa. Statefulinspection engine 514 may be configured to strip down (or rewrite)specific headers for security reasons. Stateful inspection engine 514also keeps track of latency incurred (so far) and guarantees thatsignaling latency is less than or equal to 2 milliseconds and medialatency is less than or equal to 100 microseconds.

Several real-time adjustments and tracking are performed by real-timemonitor engine 515 to ensure that the above properties are notcompromised. Specific asynchronous timer events are triggered andmonitored as new work items and engines are invoked and completed.Real-time monitor engine 515 is fully distributed and has the capabilityto open and track several live timer counters in parallel at anyinstance. If the observed time for a specific connection flow exceedsthe thresholds, real-time monitor engine 515 has full control toterminate the victim task and allows the original connection flow toproceed with the best security decision under the given circumstances.If enough slowness is observed for a large number of connection flows,real-time monitor engine 515 backpressures flow control module 502 tostop processing future incoming requests until satisfactory thresholdsare observed.

Meta-data provides an unified container mechanism by which differentprotocol parsed state values are translated into, hence providing acommon representation layer for higher application modules to operateupon. According to one embodiment, a base meta-data container includesname, AOR entries such as SRC-IP/SRC-URL, SRC-PORT, DEST-IP/DEST-URL,DEST-PORT, DATE, CONTACT, CALL-ID, CSEQ, PROTOCOL, METHOD, VERSION. Inaddition, user profiles and pointers to processing engines (e.g.,signature engine 511, DOS/DDOS engine 531, SPIT engine 532) and externalpointers to registration and location data contained in the basemeta-data container.

According to one embodiment, the present system and method detects andprotects against a suite of voice and data denial-of-service(DOS/DDOS/VDOS/VDDOS) attacks referred to as DOS attacks. DOS attacksare typically one of the two kinds: resource starvation or resourceunavailable. Resource starvation usually occurs due to flooding attacksoriginating either from a single source or multiple sources. An attackermay flood the destination server with several control packets hoggingsignificant CPU bandwidth making the server totally unusable. A DDOSattack is a variant of DOS, whereby the attacker uses multiple sourcesto collectively generate and send an excessive number of flood packetsto the victim server, often with fake and randomized source addresses,so that the victim server cannot easily identify the flooding sources.The second attack type, resource unavailable, exploits a specificvulnerability (e.g., buffer overflow attack, malformed or fuzzed inputs)on one of the networking facing processes resident on the victim server,thereby making it unusable. This often leads to a crash or anundesirable situation.

According to one embodiment, the present system and method uses a deepprotocol handshake behavior that server-client and peer-to-peer Internetapplications adhere to. Based on these distinct network protocolbehaviors, instead of monitoring just traffic rates, combined withadvanced statistical algorithms, the present system and methodaccurately detects any aberrations that violate the baseline property byemploying Change Point Monitoring (CPM) methods. The rationale behindthe CPM is that there exists a strong positive correlation betweenrequests (data) and the corresponding acknowledgment replies (ACKs), asspecified by the protocol definition, and DOS/DDOS attacks easilyviolate this property. The non-parametric CUmulative SUM (CUSUM) method,widely used in the mathematical world, detects cumulative effect of thedeviation from normal protocol behaviors caused by a DOS/DDOS attack.

According to one embodiment, the present system and method employs SPITprevention. The goals for SPIT prevention are achieving near-zero falsepositives so that normal calls go unperturbed. Tolerable false negativesare also achieved by minimizing SPIT calls going through. SPITprevention provides zero-touch solutions that involve minimalinteraction with the caller/callee to determine whether a call is SPIT.Alternatively, one-touch solutions involve interaction with the callee(or caller) on a case-by-case basis. SPIT prevention is desired to bedeployed with ease to suit different environments (e.g., office, home orremote) and to suit continual flux in an operating environment where newphones are added or removed or applications are deployed or downgraded.The SPIT prevention system combines the capabilities offered byindividual component methods so that the resulting system is able toefficiently block SPIT calls with high fidelity and minimal callee (orcaller) interaction.

Most attacks are initially preceded from reconnaissance or network andapplication discovery attacks. Specifically constructed attacks to atarget network that is not equipped with adequate protection may revealsensitive information about the network, such as servers, OSs,applications, patch version, VoIP endpoints, etc.

Application topology hiding is a relatively new concept in the VoIPworld and is a very useful defense mechanism to thwart any kind ofreconnaissance- (or information gathering) based attacks. These attacksusually run as pre-cursors to understand VoIP deployments and exploitpublicly known vulnerabilities against those infra-structure items.

To that effect, any sensitive information that is a response from aserver application either points to a topology server or is replacedwith “xxxx”. The topology server internally stores the data and rewritesspecific tag items. For example, sensitive information that is protectedby SPIT protection engine 532 include URLs/headers and parameterinformation, UC servers (e.g., IP-PBX 124, LCS/OCS, conferencing 123,collaboration, presence 122), phone extensions, user, user-groups,ports, any sensitive text or reference to VoIP installations, codecinfo, device IDs and phone numbers, and UC services (e.g., find-me,follow-me, click-2-call).

BL engine 541 and decision engine 542 provide a single focal point forall security decisions. Individual recommendations, events and hintspresented by other engines/modules working independently are furtheranalyzed by these two engines to reduce false-positives and produce ahigh fidelity result.

BL engine 541 is responsible for learning legitimate endpoint andapplication behavior in a transparent and non-intrusive way. BL engine541 comprises four phases, (1) structural analysis, (2) contentanalysis, (3) request/response traffic analysis and (4) behavioralanalysis.

Decision engine 542 adopts an unified threat assessment (UTA)methodology to correlate various meta-data information (or hints,recommendations) passed from other engines/modules in an attempt toreduce false-positives and produce a result with high fidelity. Decisionengine 542 makes the final decision, for example, whether to block,quarantine, allow or redirect (honeypot) the malicious flow stream.According to one embodiment, these options are user-configurable.

Numerous advanced algorithms ranging from Support Vector Mechanics(SVM), fuzzy logic, Bayesian algorithms and Hellinger distances areinitially used to baseline the normal behavior and compared againstruntime behaviors, i.e. per-session, per-endpoint, per-application,per-group etc.

According to one embodiment, decision engine 542 works very closely withthe remediation engines 561-564. Numerous remediation techniques may beadopted. Ping tests verify the origination sources for accuratedetection of automated war-dialing tools. Honeypot mechanism redirectssuspicious activity, voice VLAN isolation. Traffic originating from thesuspicious source (i.e. if traffic is coming inline) may be shut down.Authentication is strongly challenged and enforced using authenticatedidentity bodies.

With the true convergence of voice, video and multimedia over IP,threats coming from the data side may affect voice endpoints andsystems. In the past, data and voice have operated in separate isolatednetworks with minimal interactions therebetween, however deployment ofVoIP continues to converge voice and data.

Data validation engine 535 is responsible for ensuring that all userinputs and sensitive fields in the stream are validated with syntaxrules. Most common types of attacks in this category are buffer overflowattacks, SQL injection and cross-site scripting attacks. Buffer overflowattacks may be prevented by enforcing standard length limits on all tagelements with exceptions to override some on a case-by-case basis. Datavalidation engine consults BL engine 541 for recommended and bestpractice enforced values for a specific data value item. BL engine 541learns a priori legitimate length limits, data types, allowable rangesfor all protocol and application message elements. Data validationengine enforces that these properties observed by BL engine 541 arenever violated. Exemplary properties that are observed and enforced arethe presence of meta or script characters (e.g., ′, {,}, <script>) inthe header of the flow stream, content-length exceeding 1000 charactersand the presence of malicious SQL keywords (e.g., SELECT UNION *)

Policy manager 560 provides a framework by which UC-aware policies areeasily defined and enforced. Policies are applied at three differenthandles: users to user, user to application or vice-versa, andapplication-to-application.

Policies contain various control handles: control of the UC servicesthat an user/user-group is entitled to, control of APIs that anapplication can invoke, control of authentication, encryption and codecpolicies, control of application/application-groups to whichuser/user-groups are visible, and control of the policies that areenforced at a specific time component.

FIG. 7 illustrates an exemplary computer architecture 700 for use withthe present system, according to one embodiment. Computer architecture700 can be used to implement a UCTM system 105 with all or a part of thecomponents shown in FIG. 7. One embodiment of architecture 700 comprisesa system bus 720 for communicating information, and a processor 710coupled to bus 720 for processing information. Architecture 700 furthercomprises a random access memory (RAM) or other dynamic storage device725 (referred to herein as main memory), coupled to bus 720 for storinginformation and instructions to be executed by processor 710. Mainmemory 725 also may be used for storing temporary variables or otherintermediate information during execution of instructions by processor710. Architecture 700 also may include a read only memory (ROM) and/orother static storage device 726 coupled to bus 720 for storing staticinformation and instructions used by processor 710.

A data storage device 727 such as a magnetic disk or optical disc andits corresponding drive may also be coupled to computer system 700 forstoring information and instructions. Architecture 700 can also becoupled to a second I/O bus 750 via an I/O interface 730. A plurality ofI/O devices may be coupled to I/O bus 750, including a display device743, an input device (e.g., an alphanumeric input device 742 and/or acursor control device 741).

The communication device 740 allows for access to other computers(servers or clients) via a network. The communication device 740 maycomprise a modem, a network interface card, a wireless network interfaceor other well known interface device, such as those used for coupling toEthernet, token ring, or other types of networks.

A method and system for unified communications threat management (UCTM)for converged voice and video over IP has been described with respect tospecific examples and subsystems. It will be apparent to those ofordinary skill in the art that it is not limited to these specificexamples or subsystems but extends to other embodiments as well.

1. A computer-implemented method for real-time threat management,comprising: receiving an incoming packet; breaking the incoming packetinto sub-packets; inspecting the sub-packets using a plurality of packetprocessing engines; annotating the sub-packets with meta-data from eachof the plurality of packet processing engines; combining the sub-packetsinto an annotated packet containing the meta-data from each of theplurality of packet processing engines; processing the annotated packetusing a plurality of application engines; and generating a processedpacket.